America’s transformative legacy in Europe is great, but the transatlantic relationship is evolving—fast. Past victories in the Cold War are no guarantee of future success in the face of new probing from the restive East. In an era of finite defense resources, rising demands in Asia, and in light of the upcoming U.S. presidential elections, is the Atlantic Alliance in danger of becoming over reliant on the U.S. security umbrella? What advantages are to be gained from tighter regional cooperation through formats like Visegrád+? Can economic ties, such as energy or defense industrial cooperation sustain the transatlantic link in this new era of uncertainty?